The invention relates to the field of electrical hybridization of the propulsion of helicopters and other rotorcraft having at least one bladed main rotor, and the invention relates more particularly to a control and power supply system for at least one electric motor coupled to the turbine engine or to the main gearbox (MGB) of the rotorcraft.
In such a rotorcraft, the MGB connects an outlet shaft from the turbine engine to the bladed main rotor via a speed reducer. In addition, an auxiliary power unit (APU) serves in particular to deliver electrical power on board when the engines of the rotorcraft are stopped, in particular on the ground before they are set into rotation.
The APU is in the form of a turbine engine driving an electricity generator. This generator is designed as a starter/generator (S/G) that operates in motor mode in order to start the APU and in generator mode after the turbine engine has started and once it has reached a sufficient speed of rotation. When operating in motor mode, the S/G is powered with multiphase electricity. For this purpose, it is well known to use a direct current/alternating current (DC/AC) converter device with inverters serving to transform a DC voltage as delivered by a battery via a voltage booster DC/DC converter into AC voltages.
A major trend at present is to replace hydraulic or pneumatic power with electrical power for operating various systems in an airplane. In addition to simplifying maintenance, advantages are often sought in terms of decreasing weight and size and of reducing costs.